Native MBP battery not recognized after reconnecting

MacBook Pro 2018 13in with touch bar (board A1989 with T2 chip, 4 THB ports) only works with charger connected, but takes 1-3 minutes to boot up and is sluggishly slow with the fans revving at high speed. The system report shows no battery connected and the battery indicator top right icon doesn't appear. Every peripheral seems to work after some time and I have a proper network connection.

Now these are the main symptoms, but the problem started after investigating issues with the display. The display had died previously and I attempted a few of the suggestions like disconnecting and reconnecting the screen, etc. All of these attempts were always performed with the battery and power adapter disconnected. It is when putting everything back together that the battery issues started happening.

At this point, I am at a loss. Here is a recap:

1. Does not boot from the battery
2. Power cable is required for operation
3. Takes 1-3 minutes to boot and is extremely slow
4. Fans rev at high speed
5. Battery appears absent from system report

What I have tried so far:

1. Cleaning the battery connector contacts
2. Performing SMC reset (the right way for a T2 chip)
3. Booting on power adapter with battery disconnected, shutting down and booting from battery without power adapter (suggested from a post down below)
4. I also checked the voltage on the battery control board (the +/- contacts where the connector sits) which showed zero volts.
5. Assuming the battery was drained, I tried leaving the macbook connected to mains for a few hours before performing the previous steps once more.
6. I visually inspected the logic board for damage and there is nothing at all that looks out of place..

If anyone could shed some insight other than "replace your battery" or "go get a new computer", that would really be appreciated! Also, I am not afraid of highly technical advice. I cannot believe this 2600$ piece of equipment is irrecuperable...

The previous post that best matches my problem description (except the battery type), is this one: New battery not recognised in MacBook Pro 13(early 2015) Again, that did not fix my issue.